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The results of numerical simulation of downward solar radiation fluxes for background and smoke-contaminated atmospheric conditions are discussed. Vertical profiles of aerosol characteristics are obtained from the empirical model based on the data of aircraft sounding of profiles of angular scattering coefficients and content of absorbing particles in the lower troposphere. The background model was created using the results of measurements obtained under cloudless and mostly cloudless atmospheric conditions in 1999–2011. Optical parameters of smoke aerosol are determined from the data of aircraft measurements in the period of long-term wildfires in Siberia in the summer 2012. It is demonstrated that deficiency in diurnal values of total solar radiation at the surface level caused by the formation of the optically dense smoke layer as compared to background conditions, is more than 13 MJ/m2.  相似文献   
997.
The spatial distribution of methane content and methane fluxes in the water in the north-western part of the Sea of Japan, in the Kuril basin of the Sea of Okhotsk, and in the near-Kuril part of the Pacific Ocean is studied using the data of marine research expeditions in 2005, 2010, and 2011. The studies revealed the significant variability of the methane flux depending on the source presence and on the sea surface conditions. The high emission of methane from water to the atmosphere is registered in the areas where its concentration exceeds the equilibrium values with the atmosphere. The use of the model of computation of the fields of currents and contaminant transport for the investigated water area enabled explaining the formation of the high concentration of methane in the center of vortices in the zones of sea water convergence in the water areas under study.  相似文献   
998.
Based on the global aerological dataset and on the method for determination of the boundaries and amount of cloudiness using the profiles of temperature and humidity obtained from the atmospheric radiosounding data [23], the estimates are computed for the parameters of atmospheric temperature- humidity separation into cloud and intercloud layers from the surface to the height of 10 km. The base and top of cloud layers and their total thickness and frequency are selected as layering parameters. The computations are based on the data for the observational period of 1964-1998. To specify the spatiotemporal features of atmospheric layering, long-term geographic distributions of mean values and standard deviations of the mentioned parameters are constructed for January and July, and the amplitude of their variations is determined.  相似文献   
999.
Investigated is the periodic component of geoacoustic emission within the frequency band from 2.0 to 6.5 kHz registered by the piezoceramic hydrophone installed near the bottom of Lake Mikizha in the Kamchatka Peninsula. It is revealed that the variation period is 24 hours and the maximum variation is observed in summer, when the average daily air temperature is above 10°C. In that period the close connection is revealed between the series of air temperature and geoacoustic emission. Taking into account the similar results of measurements of the ground surface slope at the observation site, the most probable reason for the diurnal variations of high-frequency geoacoustic emission is the deformation of near-surface sedimentary rocks caused by diurnal variations of temperature.  相似文献   
1000.
The methods are considered to solve the problem of secure isolation of radioactive waste containing long-lived products of nuclear fuel processing with a half-life of tens of thousands years (plutonium etc.). The methodology of long-term projection of average annual surface air temperature and total precipitation is proposed. Taking into account the possible scenarios of the development of the global socioeconomic system, variations due to the anthropogenic impact in average annual temperature at the Northern Hemisphere mid-latitudes for the period till 2300 are estimated. Based on paleoclimatic data, projections of natural trends in global average annual temperature and total precipitation till the year 3000 are developed. Taking into account the anthropogenic component, the projective ranges of these climatic parameters in the Vyatka River basin in 2100-3000 are evaluated.  相似文献   
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